Searing images of the U.S. under attack

In an effort to capture 9/11's terrifying cocktail of chaos, carnage and grief -- not easy to remember, but impossible to forget -- editors at Life.com have collected "the 25 most stirring, visceral photographs from that day": images that show everything from the "surreal inferno" of a burning building to dust-caked survivors whose faces reflect their fundamental pain, disbelief and disorientation.

The following slide show offers a selection of these photographs; you can visit the full Life.com gallery here.